Continuously cast products, in particular slabs, are subjected to surface treatment by grinding after continuous casting in order to obtain an adequate quality during the further processing of the product. In the grinding of continuously cast slabs, the slab is usually longitudinally reciprocated under a grinder (grinding unit). At the end of each reversing movement, the grinder is transversely indexed until the entire slab surface has been ground.
During grinding, the slab is supported lying on its long broad side on a grinding table.
A prior-art generic apparatus for grinding slabs is shown in FIG. 1. It is similar to that described in EP 053274.
So-called HP grinding (High-Pressure Grinding) of the slab 1 is carried out on the apparatus shown in FIG. 1. The apparatus has a grinding table 13 as well as a grinder 9 with a drive motor 10 and a grinding wheel 6. The slab 1 has in the known manner two wide side faces 2 and 3 (long sides) and two narrow edge faces 4 and 5 (short sides). It rests with one of its wide side faces 3 on the grinding table 13. During grinding of the surface of the slab, the grinding table 13 reciprocates longitudinally under the grinder 9 in a direction perpendicular to the drawing plane. The grinding wheel 6 is pressed against the surface of the slab 1 by a grinding pressure cylinder 14. The slab 1 is thus moved back and forth in the longitudinal direction relative to the grinder 9 by the grinding table 13. With each reversing movement, the grinder 9 is transversely indexed by a feed cylinder 15, until the surface of the slab has been completely ground.
The disadvantage is that, positioned with the broad side on the grinding table 13, the slab 1 has a minimal areal moment of inertia relative to an axis that is horizontal and transverse to the longitudinal axis of the slab. Accordingly, resistance to bending about this axis is minimal. In particular during grinding of a slab at a high temperature (for example up to 800° C.), there is therefore a danger of bending. The grinding table 13 is therefore provided at predetermined spacings along the longitudinal axis of the slab 1 with stops 16 are intended to minimize bending of the slab. The number of the stops 16 is selected to be correspondingly high for this purpose. However, this has the negative result of a relatively massive and heavy construction of the grinding table.
Slabs at average temperatures (in the range of 450° C., for example) bend upward due to the higher temperatures at their lower horizontal main side at the ends of the slab. This leads in a disadvantageous manner to the slab tending toward undesirable vibrations during grinding with the positioning shown during grinding. In this case, the slab 1 rests above all on central supports 13.
Slabs cooled to workshop temperature are therefore also as a rule not planar on their broad sides.
Another problem lies in that considerable deposit of grinding chips on the apparatus can occur when flying chips are not contained optimally during grinding. Therefore a relatively high maintenance expenditure is necessary with solutions previously known in order to keep the apparatus in optimal use condition.